Holding means for metal-working machines.



H. G: DAVIS.

HOLDING MEANS FOR METAL WORKING MACHINES.

A TTORNE YS.

Patented July 17, 1917.

4 SHEETS-SHEET 1 APPLICATION FILED JUNE 24, IBIS.

H. G. DAVIS.

HOLDING MEANS FOR METAL womuws MACHINES.

APPLICATION FILED 111N524. I915- Patented July 17, 1917.

4 SHEETS-SHEET 2- IN VEN TOR.

A TTORNE YS.

WITNESS H. G. DAVIS.

HOLDING MEANS FOR METAL WORKING MACHINES.

APPLICATION FILED JUNE24, 1915.

Patented Ju1y17,1917.

4 SHEETS-SHEET 3.

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WITNESS I 'INVENTOF. fikmwzz 6m A} TTORNEYS.

H. e. DAVIS.

HOLDING MEANS FOR METAL WORKING MACHINES.

APPLICATION FILED JUNE 24. 1915. 1 1; 3,5 Patented July 17, 1917.

' 4 SHEETSSHEET 4 aka/0% \M.

IN VEN TOR M150 dim ATTORNEYS.

WITNESS I EENnEESoN o. navrs; or'wEsT SPRINGFIELD, MASSACHUSETTS, assIeNon To GIL- BERT a EKEE .MANUEACTUIIRING COMPANY, 0E WEST SPRINGFIELD, MASSA1 CHUSETTS, A ooEromTIoN or MASSACHUSETTS.

HOLDING- MEANS FOR METAL-WORKING MACHINES.

L233AL53.

fipeolflcatlon of Letters Patent.

Patented July W, iait.

Application filed. June 24%, 1915. .Serial No. 86,146,

To all whom it may concern: 7 I

Be it known that LHENDERSON G. DAVIS, a citizen of the United States of America, and residin county of ampden and State of Massachusetts, have invented certain new and useful Improvements in Holding Means for Metal-Working Machines, of which the following is a specification.

This invention relates to an improved clamping device for metal workin apparatus, and, while the invention is, capable of general application, it is particularly adapted for use in seam welding apparatus. In my co-pending application Senal No. 7 64,530, filed April 30, 1913, I havedlsclosed a welding apparatus for supporting work and holding work to be welded. This indial work-supporting arms secured thereto.-

vention is especially designed to be applied to and to cooperate with this work-supporting apparatus and to provide an improved clamping means for firmly holding the edges of the work to be welded,

In the above-mentioned application, a supporting stand is provided, which has a central rotatable head with a plurality of ra- Each of these arms has a longitudinal groove tilt welded, the apparatus is necessarily large therein overwhich the edges of the seam to be welded are positioned and, adjacent the groove on either side thereof, holdin means are employed to clamp the work to the arms. The holding means employed comprises a bar extending the length of the -work-supporting arm and arranged to overlie the metal to be welded. This bar is pivoted at one end so that it can be swung outwardly to permit work to be welded, such as, a shell for example, to be moved inwardly upon or outwardly from the work-supporting arm- After the shell is suitably positioned on the arm, it is held by one or more operators while other operators swing the bar back into position and clamp the same against the shell. The clamping is accomplished by two bolts and hand nuts arranged one ateither end of the bar.

While the clamping device just described accomplishes its purpose if proper care is used by the operators, it is not entirely satisfactory in practice on account of the time and large number of operators required .for its manipulation. When large shells are at West Springfield, in the the entire length of the Furthermore, it is desirable to quickly clamp shell at one time, which was impractical with the former clamping bar since each end of the latter had to be independently forced a ainst the shell by hand. The pressure of t e clamping bar on the shell was obtained sii'npl by hand tightening of nuts at each end oi: the bar and. was not of uniform intensity throughout the length of the bar. Between the points of application of the clamping pressure and especially near the central portion of the shell, the pressure was of a much smaller and, oftentimes, inadequate value. These disadvantages I seek to remedy by my invention.

An object of the invention is to provide in an apparatus of the claw described an improved clamping device, which is operable simultaneously to clamp all points along the seam to be welded. -Another object is to provide a clamping bar and automatically operable means, applied at a plurality of points along the bar, to force the latter against the metal to be welded and the supporting arm for the metal. Another object is to provide an improved clamping upon the arm and is thereafter quickly and easily operable to clamp each edge of the shell against the arm. A further object is to provide a clamping arm and operating mechanism therefor which is of simplified and generally improved mechanical structure.

With these objects in view a single preferredembodiment of my invention is shown, for the purposes of illustration in the accompanying. drawings, in which- Figure 1 is a plan view of the clamping device as applied to a work-supportingstand showing the general arrangement of the structure;

Fig. 2 is a side elevational' view thereof; Fig. 3 is a cross-sectional view on an enlarged Scale taken on the line 3-3 of Fig. 1 and looking in the direction of the arrows; Fi 4 is a cross-sectional view taken on the line 4-4 of Fig. 1 and looking in the direction of the arrows;

. Fig. 5 is a plan view of a part of the clamping device shown removed from the supporting apparatusi Fig. 6 is a cross-sectional view taken on the line 6-6 of Fig. 1 and looking in the direction of the arrows;

Fig. 7 is a partial longitudinal section taken on the line 77 of Fig. 6; and

Fig. 8 isa sectional elevation of the manifold for distributing compressed air to the clamping devices.

Referring to these drawings in detail and particularly to Figs. 1 and 2: a represents the central rotatable head of a work-supporting stand such as is fully described in the above-identified application. Secured to the head a and extending radially outward therefrom are a plurality of work-supporting arms I). These arms have the general cross-sectional shape shown in Figs. 3 and 4 and are formed with a central longitudinally arranged groove 0, which directly underlies the seam to be welded. The seam is welded by another machine which overlies two of the supporting arms 6 and which has traveling welding torches movable along the seam over-the groove 0. The arrangement of the supporting stand is such that shells may be placed in position on and clamped to two of the arms I) while other shells on the other two arms are being welded. Thus, when the latter shells are welded, the head a may be rotated to bring the two unwelded shells, previously positioned and clamped on the arms 12, into position beneath the welding torches. The structure just described is substantially similar to that. disclosed in the above-identified co-pending application. The mechanism associated with the arms I), as shown in my 'prior application to which reference has been made, has not been illustrated here. The clamping mechanisms on each arm I) are exactly the same and the structure for a single arm only will be described.

' Secured to the inner end of the arm I) and arranged transversely with respect to the groove 0 is a member 1 (See Fig. 4). The latter is securely held to lugs on the arm 6 by bolts 2 and is arranged to bridge the groove 0 and extend outwardly on either side of the arm as shown. Secured to each end of the bridge 1 by the bolts shown is a bar 3 which parallels the arm I) and extends to the outer end thereof. Each bar 3 is provided at intervals with an upstanding cylinder 4 open at the top and adjacent each cylinder are a pair of spaced upstanding webs 5, which extend inwardly toward the groove 0. Rotatably mounted in the upper part of each of these webs 5 is a shaft 6 WlllCh extends from one end of the bar 3 to the other and connects all of the webs 5 on each bar. Mounted on the inner ends ofthe shafts 6 and held in place by the collars shown are T-castings 7 (see Fig. 1) and-extending between these castings is a rod 8 which serves to tie the two shafts together transversely. On the outer end of the shafts 6 are similar T-castings 9 and a similar transversely ar-. ranged tie rod 10.

Pivotally mounted at 11 in a casting 11 secured to the outer end of arm I) is a lever 12 which has a fork 13 formed at its upper end (see Figs. 6 and 7). The arms of this fork are arranged to engage and support the rod 10 in a removable manner. Fixed to the rod 10 and spanning the fork 13 is an upwardly extending member 14 having an eye 15 therein. Normally the fork 13 supports the rod 10,but, when a shell is to be placed on or removed from the arm I), the rod 10 is supported from the eye 15 by any suitable means, such as, a hook, rope, or chain falls, for example. Thus, the lever 12 may be withdrawn to leave a free passage for the movement of the shell axially along the arm. It is to be noted that the bars 3 are spaced from the arm I) to permit axial movement of a' shell along the arm. These bars 3 are 'tied together into a fixed framework by the shafts 6 and rods 8 and 10, and this framework is fixed at its innermost end to the bridge 1 and at its outer end is normally supported and held in proper spaced relation above arms I) by the movable lever 12.

Each bar 3'is provided with longitudinal passages 16 (see Figs. 3 and 5) which are cored in the reinforcing web extending between the several cylinders 4. These passages serve to connect all of the cylinders on the respective bars 3. The innermost cylinders 4 of each bar are connected by pipes 17 through suitable twoway valves 18 to a radially arranged pipe 19, which leads to a manifold 20. The latter is best shown in Fig. 8 and is formed with a common chamber 21 into which each pipe 19 leads. A main supply pipe has mounted therein a Suitable piston 26 and secured to the latter are upwardly extending forked arms 27. Fixed to the shafts 6 between-each pair of webs are levers 28 which" are pivotally connected at one end to the forked arms 27 and at the other end to other forked arms 29. Each group of the latter (comprising five as illustrated' in Fig. 1) are secured as shown in Fig. 3 to a T-shaped clamping bar 30. Formed on the latter adjacent each cylinder 4 are projections 31 which are arranged to .enga e the surfaces 32 on the webs 5, as clear y shown in Figs. 3, 4, and 6. The bars extend the length of arm I) .and parallel the groove 0, closely adjacent'the edges thereof. The arm 6 has slightly raised therefrom clamping surfaces 0, and, when a shell is inserted between these surfaces 6 and ,the clamping. bars 30, the surfaces 33of the latter are arranged to force the shell against the surfaces 6.

Fixed to each shaft 6 near the central portion thereof is a lever 34: which is arranged for hand operation to depress all the pistons 26 in one row, when the shell is to be released previous to its withdrawal from arm I). A pin 35 in each lever 34 (see Fig. 3), actuated by a spring 36, is arranged to engage a suitable recess in the web of each bar 3 to hold the clamping bars 30 inthe lifted position shown in the drawings.

In operation, assuming the clamping bars 30 to be in lifted position, as shown in the drawings, a hook, chain falls, or other suit: able device arranged above the apparatus is attached to the eye 15 to temporarily support from above the outer ends of the bars 3.

The lever 12 is then withdrawn and the inclination of the jaws of fork 13 is such as to permit this movement. There is then a free axial passage between the clampin bars 30, and the clamping surfaces e 0 arm I), and a shell is slip ed onto the arm from the outer end thereof The lever 12 is then replaced in the position shown in Fig. 7 and, when so positioned, is prevented from moving outwardly due to the weight imposed on the inclined jaws of fork 13, as

the line of action of the force on the jaws lies to the right of the pivot 11 as viewed in Fig. 7..

An operator next alines ,one edge of the shell to be welded centrally of the groove 0 and, after it is once properly positioned,,

another operator operates the appropriate valve 18. Compressed air is then admitted simultaneousl to all of the cylinderst on one bar 3 an the levers 28 are thus 0 erated in an obvious manner to force the ar 30 downwardly, whereby one edge of the shell is clamped between the surfaces 33 and e. The other edge is then adjusted, alined,

and clamped in a similar manner. The seam is then welded. During the welding operation, hel ers may be emplo ed in placlng other she s upon the two ree arms b so that, after the first two shells are welded,

two others will be immediately available upon the rotation of the head a through ninety degrees.

When a welded shell is to be removed,

the valves 18 are turned to-close oil the supply and to permit the escape of air from the cylinders 4. The levers 34 are then depressed by the operator to lift the bars 30 and depress the pistons 26. The pins 35 thereafter hold the bars in lifted position, as already described, and the shell may then be removed after the lever 12 has been withdrawn.

Thus, an improved operable clamping mechanism, automatic to a degree, is pro- Vjded which is arranged for quick and convenient operation and which requires a small amount of labor and a minimum amount of effort on the part of each operator. Instantaneous clamping of the work along its entire length and with a substantially uniform pressure is made possible by this device. The proper and convenient clamping of the work to be welded necessarily insures an improved welded seam, and thus not only is the Work done conveniently but the quality of the work is improved. -It is recognized that various modifications may be made in the structure heretofore described without departing from the scope of my invention which is pointed out and defined in the appended claims.

What I claim is a 1. The combinationwith a support, of a radial overhanging arm secured thereto and arranged to support work to be welded,

clamping bars mounted above and movable in'parallel relation with said arm and arranged to clamp the two edges of the work to said arm with the seam to be welded between said bars, a series of devices for each bar, the devices of each series spaced along said arm and connected for simultaneous actuation of its bar from a single point, whereby the edges of the work to be welded may be instantaneously clamped at every point in its length with a uniform pressure, and a controlling means for each series of devices.

2. The combination with a supporting stand, of a plurality of radial arms secured lilo thereto in overhanging relation and each welded, of clamping bars arranged above and in parallel relation with each arm, said bars arranged to clamp the two edges of the Work to an arm with the seam to be welded disposed between said bars, a series of cylinders for each bar spaced along the length of its arm, pistons for said cylinders, operative means connecting each bar with all of the pistons in its series of cylinders, and means to admit compressed air simultaneously to all the cylinders in each series, all constructed and arranged so that each bar may be actuated independently of the other to clamp the work to an arm with a uniform pressure.

3. The combination with an arm adapted to support work to be welded, of a frame arranged above said arm, supporting devices at each end of the framework arranged to hold the latter in spaced relation from said arm, one of said devices arranged to permit work to be welded to be placed on and removed from said arm, clamping bars movably mounted on said framework, said bars arranged on either side of said arm and in parallel relation therewith, and means to actuate either or both of said bars, whereby the edges of the work to be welded may be clamped against the arm by said bars with the seam to be welded therebetween.

4. The combination with an arm adapted to support work to be welded, of a frame- I work, means to support the latter in spaced relation from said arm arranged to permit work to be welded to be slid longitudinally alongthe arm from the outer end thereof, two groups of cylinders mounted on said frame, pistons therefor, two clamping bars 1 movably mounted on said frame, said bars arranged one on each side of the longitudinal axis of said arm and in parallel relation therewith, connections between each bar and all of the pistons of its group of cylinders, and means to actuate all of the pistons of one group simultaneously, whereby each bar may be forced downwardly to clamp each edge of the work to be welded against said arm.

5. The combination with a supporting stand including a rotatable head and a plurality of radial work sup orting arms secured thereto, of clamping ars arranged on either side of the longitudinal axis of each of said arms and in parallel relation therewith, said arms arranged each to clamp an edge of the work to sald arm with the seam to be welded disposed between the bars, a group of cylinders for each bar, pistons'for the cylinders, operative connections between each bar and all of the pistons in its group of cylinders, connections between all of the cylinders of each group, a valve for each oup, a manifold on said head, connections om the valves to said manifold and a connection from a supply of fluid under pressure to said manifold, all constructed and arranged so that each bar may be actuated independently of the others by a group of pistons and so that said arms and head may e rotated without interrupting the supply to said manifold.

6. The combination with an arm adapted to support work to be welded of two spaced parallel members mounted on and spaced from said arm and arranged to permit work to be welded to be slid longitudinally along the arm beneath said members, clamping bars movably supported on said members, each arranged to clamp an edge of the work to be welded to said arm, and a series of devices for each bar' arranged to simultaneously actuate the latter at several points along its length to clamp the work to said bar.

7. The combination with an arm adapted to support work to be welded, of a frame work, means to support the latter in spaced relation from said arm arranged to permit work to be welded to be slid longitudinally along the arm from the outer end thereof, two groups of cylinders mounted on said frame, pistons therefor, two clam'pin bars movably mounted on said frame, sai bars arranged one on each side of the longitudinal axis of said arm and in parallel relation therewith, connections between each bar and all of the pistons of its group of cylinders, means to actuate all of the pistons of one group simultaneously, whereby each bar may be forced downwardly to clamp each edge of the work to be welded against said arm, a lever operably connected to HENDERSON G. DAVIS. 

